<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <link href="https://cdn.bootcdn.net/ajax/libs/normalize/8.0.1/normalize.min.css" rel="stylesheet">
    <title>flex布局</title>
    <link rel="stylesheet" href="./access/iconfont.css">
    <style>
        .nav{
            position: fixed;
            width: 100vw;
            height: 10vh;
            background-color: #eee;
            bottom: 0;
            left: 0;
            border-top: 1px solid #ccc;
            padding: 0;
            margin: 0;

            display: flex;
            flex-direction: row;
            justify-content: space-between;
        }
        li {
            list-style: none;
            flex: 1;
            display: flex;
            justify-content: center;
            align-items: center;
            transition: all 0.2s;
        }
        li .iconfont {
            font-size: 28px;
        }
        li:active{
            opacity: .5;
        }
    </style>
</head>
<body>
    <ul class="nav">
        <li class="btn">
            <i class="iconfont icon-chuangzuo"></i>
        </li>
        <li class="btn">
            <i class="iconfont icon-ertongpiao"></i></li>
        <li class="btn">
            <i class="iconfont icon-huiyuan"></i></li>
        <li class="btn">
            <i class="iconfont icon-aliyu"></i></li>
    </ul>
</body>
</html>